Uh, this isn't a paste, but really related. When I am using Steam chat - or any chat really - and am typing a message and suddenly need to start another one, I do a quick Ctrl-A + Ctrl-X to copy the current into the buffer to continue it later. After sending that, I would do Space + Ctrl-A + Ctrl-X to copy the space character into the buffer, to not accidentally paste that elsewhere irrelevantly.
But now this is a really really really obtrusive habit that my hands keep following whenever I press enter to send a message, and also every half a minute I spend looking at the chat, and sometimes just whenever. I'm really fucked on this, lol.
So yeah this doesn't work for me, 90% of the time I'd press Ctrl-V without doing anything particular I'd end up writing a space.
Edit: fuck, even after doing edits to this message I keep switching to discord to do the space-copy thing there. help